Simple Network Management Protocol (SNMP) Video Lecture | Computer Networks - Computer Science Engineering (CSE)

hello again as you know I'm you like a
computer guy over here for Eli the
computer guy calm and everyman itea calm
today's class is introduction to SNMP
simple network management protocol this
protocol allows you to proactively view
what's going on on the devices in your
network and fix issues before they
become major problems if you are in an
environment where you can do proactive
maintenance SNMP is a major major great
wonderful thing SNMP is usually a
component used in a larger software
package so if you use something like
Spiceworks to monitor your network or
open manager or land view or one of
those pieces of software they will use
the SNMP protocol in order to
communicate with all the devices on the
network and gather information from them
so SNMP is generally it simply a
component of a larger software package
this class we're going to go over what
SNMP is why it is just about the most
wonderful thing since sliced bread and
give you an idea of how you can use it
on your network so if you give me a
second we'll dive into this class
introduction to SNMP simple network
management protocol
so let's talk about SNMP s and M P again
simple network management protocol and
why it is so awesome now the first thing
to remember that is that SNMP is always
going to be used and as a component of
another piece of software so the
software is going to be some kind of
network management software again
something like land view or Spiceworks
basically this software goes out and it
takes a look at the network and can show
you what's going on with all the devices
and computers in your network well one
of the ways it's able to gather
information is through SNMP the simple
network management protocol why this is
so great is because you can get a lot of
information from the device in real time
about what is going on with the device
on the network so normally if you use
some of this there's this network
monitoring software you know it can use
a ping command in order to see if the
computer is active it can do a few other
things to see if the computer is on the
network you know what IP address it is
what host name it is etc what SNMP
allows you to see what's going on in the
computer it can see how uh how much of
the hard drive space has been used it
can sitt it can see how much of the CPU
is currently being used etc beyond that
it can actually see what's going on with
the hardware on your computer so things
like whether or not the fans in the case
are working properly whether they're
running at all whether the memory slot
is working properly etc SNMP simple
network management protocol is what is
able to send this information back to a
management console now if you're you're
a new person in computers again you're
probably thinking if you had five or ten
computers that's a lot of computers well
remember when I was
in the enterprise world we did one
deployment simply for a new application
that was 200 servers we brought on line
in a week
that wasn't our entire data center that
was just for one application that we
brought online 200 servers and all those
servers had to be up and running so the
big question is is if you want to make
sure all your servers are up and running
you need to make sure that the case fans
are working properly the hard drives are
working properly CPU fans are working
properly etc if you've got 200 servers
or thousand servers you can't simply
walk through and open up every case
every day to make sure everything's
working right well with SNMP that
information can be sent back to a
management console and you can see that
there is an issue before it becomes a
major problem so the case fan fails in a
server that's not going to destroy your
server it's just simply the case fam but
if the server cannot cool itself the
heat within the server gets too high
well then it can destroy the server it
can destroy the hard drives it can
destroy CPU etc but you do have a window
before the heat builds up and destroys
the components in the server if you have
this s and NP running as soon as that
case fan fails it will send an alert
back to the management console and then
the management console will give you an
alert that says server number of 564
case fan just failed you can go
oh crap and you can grab a case fan and
you can run out to two server 564 and
replace the case fan and everything
works just great that's the major use
for SNMP is for these preventive
maintenance type things you can set
alerts for if 80% of somebody's hard
drive is used then set an alert to you
to tell you so that you can give them a
bigger hard drive if their CPU is always
above 90% that they can send an alert to
you so you can
fix the problem before the user notices
there's a problem or before the server
or application or whatever fail that's
that's just what makes SNMP great so
when you're dealing with SNMP simple
network management protocol again this
is going to be built into another
application some kind of network
monitoring application so when you're
dealing with SNMP the first thing you
have is some kind of management computer
so on this management computer you'll
have some kind of operating system and
then you will install the SNMP
management software so this is where all
of the alerts are going to go back to so
all the computers on the network where
you have this set up will send
information back to this management
console and then this management console
will decide what to do will it simply
pop up with an alert on the screen will
it email you an alert you know will an
email corporate headquarters of alert
that will all be decided based on rules
on this management console then for all
the devices on the network that are
using the SNMP software you will install
an agent so this agent is simply a
little piece of software that is able to
read information on the device and then
send that information back to the
management console
sometimes agents nowadays are already
installed onto the device and now Dell
and some of the other major vendors of
computers actually have what are called
agentless SNMP where the agent is built
into the hardware itself so the
important thing is you do have to have
this agent but it may already be built
into the computer or into the hardware
if it is not you simply install the
software onto the computer so if you
were going to use you know one of these
network management software you would
install a management console onto your
one main compute
we're going to read all the information
and then you go out to all the
individual computers or devices on the
network and you install the agent now
once you have done that if you sit down
at this management console you can then
connect to any of these computers and
see the information so you can see that
80% of the hard drive is used or you can
see that currently the CPU is running at
50% etc etc etc so that's when you
simply sit down well if you on the agent
if you set what is called a trap this
trap is a way to alert the month
management console when a rule has been
broken so you could say when the hard
drive space goes above 80% alert the
management console that is a trap
traps are alerts that actually alert the
management console when an event happens
so if the CPU fan fails you can create a
trap which will send that information to
the management console the management
console will then show you the
administrator Oh
PC number 578 CPU fan fail and that's
really all there is to it it is it is it
is very simple but very easy so you have
a management computer you install the
management software on then on the
devices or computers you're going to be
monitoring you install the agent at this
point the management console can connect
to the agent and see what's going on in
real time but if you want to create an
alert where this computer will alert the
management console when there is a
problem that you decide you set what is
called a trap when that trap when the
rule for that trap is met that will then
send information to the management
console and you will be alerted with
what is going on and that's really all
there is the SNMP simple network
management
article again this will be built into a
bigger application you know Spiceworks
land view whatever some kind of network
monitoring software and then this is
what happened so SNMP is a major
protocol just like tcp/ip is so it's a
major protocol there's a whole bunch of
documentation onto it
it's built into this larger software you
install a management console you install
the agent you set traps to send the
alerts a couple the big things with this
if you decide to use software that uses
SNMP is that there is an SNMP service on
your windows computer and if you disable
that service your SNMP software will not
work properly so if you install this
management software and it's not working
make sure the proper services have been
started back a few years ago in the old
XP days hackers were able to manipulate
the SNMP service on Windows computers
and cause you all kinds of problems
sending messages and all kinds of nasty
stuff so some administer administrators
disable the SNMP ste SNMP service so
just make sure it's actually set up and
running and then this is a protocol
simple network management protocol so
since it's a protocol it uses networking
ports if you have firewalls set up on
your network or on your individual
computers they may block the ports that
are required for this service so make
sure whenever you're setting this SNMP
software up that all the ports are open
you can use different ports depending on
what software you're using so you just
look into the documentation and see
what's going on if you have some kind of
Internet Security Suite on these
computers you're going to need to make
sure the ports are open so that all the
information can get sent back to the
management console so that's really all
there is to SNMP
so that's all there is to SNMP or simple
network management protocol this is a
protocol that gets built into large your
software network monitoring software the
important thing to remember is you
install a management console on one
computer so that's going to be your
management server then you install the
agent software on all the computers that
are going to be monitored and then if
you want real-time alerts going back to
the management console you have to set
what is called traps how old has done is
done
completely depends upon the software
that you're going to be using but
believe me I messed around with this and
learn this the hard way if you
understand these concepts using the
software is going to be easier if you
just walk in and try to use a software
off the bat it's just really really
confusing so as I say especially if
you're going into the enterprise world
this is amazingly wonderful just better
than sliced bread the reason is is
because if you're deploying 100 or 200
servers at a go again you're not going
to be able to check the fans in every
computer you're not going to check every
memory slot especially with these new
larger servers that support over 200
gigs of ram they may have 20 memory
slots how are you to know if one single
memory slot in the 50th server fails
well you wouldn't unless you're using
this monitoring software that would use
SNMP it would give you the alert and
then you could figure out what is going
on again I've used this stuff a lot in
the real world it is just absolutely
wonderful if you want to go out do a
Google search on SNMP and you will
simply get tons and tons of different
software packages that will be available
to you so the SNMP is simply going to be
a component of those software packages
some of them are open source some of
them are free some of them don't cost
very much and some of them are just
ridiculously horribly expensive again in
the IT world it all depends on what you
need you know if you're dealing with
some nonprofit organization you guys
have 40 pcs you might be able to get
away with
downloading some free SNMP software
simply to monitor those pcs and make
sure they're working okay if you go into
an enterprise environment and you're
dealing with you know ten thousand
twenty thousand systems well then it
might be worth paying 50 or $100 per
agent for some SNMP software it may save
you more money at the end of the day but
this is all SNMP is the only warnings
that I will give you on it is again
remember SNMP uses services on your
Windows computer some administrators
disable those services just you know to
protect the computers so if you're
coming in behind another administrator
and you try to set this up it may not
work properly because they may have shut
off the services that are required for
the SNMP all you have to do is look in
the documentation of the software see
what services have to be started and
then start those services on each and
every computer so that that will take a
little while and then remember this is
also a protocol just like tcp/ip simple
network management protocol all of
networking protocols use different ports
SNMP can use a number of different ports
so again look in the documentation of
the software and see what that
particular software uses for the port's
if you have firewalls enabled on the
individual computers or somewhere in the
network those the SNMP traps may not be
able to send information because you
block ports so just be careful of that
so that's that's really all there is to
this class introduction to SNMP simple
network management protocol as always
I'm Eli the computer guy over here for
Eli the computer guy comm and every man
IT comm I enjoy teaching this class and
look forward to see you at the next one